/**
 * Roundcube List Widget
 *
 * This file is part of the Roundcube Webmail client
 *
 * @licstart  The following is the entire license notice for the
 * JavaScript code in this file.
 *
 * Copyright (c) The Roundcube Dev Team
 *
 * The JavaScript code in this page is free software: you can
 * redistribute it and/or modify it under the terms of the GNU
 * General Public License (GNU GPL) as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option)
 * any later version.  The code is distributed WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU GPL for more details.
 *
 * As additional permission under GNU GPL version 3 section 7, you
 * may distribute non-source (e.g., minimized or compacted) forms of
 * that code without the copy of the GNU GPL normally required by
 * section 4, provided you include this license notice and a URL
 * through which recipients can access the Corresponding Source.
 *
 * @licend  The above is the entire license notice
 * for the JavaScript code in this file.
 *
 * @author Thomas Bruederli <roundcube@gmail.com>
 * @author Charles McNulty <charles@charlesmcnulty.com>
 *
 * @requires jquery.js, common.js
 */


/**
 * Roundcube List Widget class
 * @constructor
 */
function rcube_list_widget(list, p) {
    // static constants
    this.ENTER_KEY = 13;
    this.DELETE_KEY = 46;
    this.BACKSPACE_KEY = 8;

    this.list = list ? list : null;
    this.tagname = this.list ? this.list.nodeName.toLowerCase() : 'table';
    this.id_regexp = /^rcmrow([a-z0-9\-_=\+\/]+)/i;
    this.rows = {};
    this.selection = [];
    this.rowcount = 0;
    this.colcount = 0;

    this.subject_col = 0;
    this.modkey = 0;
    this.multiselect = false;
    this.multiexpand = false;
    this.multi_selecting = false;
    this.draggable = false;
    this.column_movable = false;
    this.keyboard = false;
    this.toggleselect = false;
    this.aria_listbox = false;
    this.parent_focus = true;
    this.checkbox_selection = false;

    this.drag_active = false;
    this.col_drag_active = false;
    this.column_fixed = null;
    this.last_selected = null;
    this.shift_start = null;
    this.focused = false;
    this.drag_mouse_start = null;
    this.dblclick_time = 500; // default value on MS Windows is 500
    this.row_init = function () {}; // @deprecated; use list.addEventListener('initrow') instead

    this.touch_start_time = 0; // start time of the touch event
    this.touch_event_time = 500; // maximum time a touch should be considered a left mouse button event, after this its something else (eg contextmenu event)

    // overwrite default parameters
    if (p && typeof p === 'object') {
        for (var n in p) {
            this[n] = p[n];
        }
    }

    // register this instance
    rcube_list_widget._instances.push(this);
}


rcube_list_widget.prototype = {


    /**
     * get all message rows from HTML table and init each row
     */
    init: function () {
        if (this.tagname == 'table' && this.list && this.list.tBodies[0]) {
            this.thead = this.list.tHead;
            this.tbody = this.list.tBodies[0];
        } else if (this.tagname != 'table' && this.list) {
            this.tbody = this.list;
        }

        if ($(this.list).attr('role') == 'listbox') {
            this.aria_listbox = true;
            if (this.multiselect) {
                $(this.list).attr('aria-multiselectable', 'true');
            }
        }

        var me = this;

        if (this.tbody) {
            this.rows = {};
            this.rowcount = 0;

            var r, len, rows = this.tbody.childNodes;

            for (r = 0, len = rows.length; r < len; r++) {
                if (rows[r].nodeType == 1) {
                    this.rowcount += this.init_row(rows[r]) ? 1 : 0;
                }
            }

            this.init_header();
            this.frame = this.list.parentNode;

            // set body events
            if (this.keyboard) {
                rcube_event.add_listener({ event: 'keydown', object: this, method: 'key_press' });

                // allow the table element to receive focus.
                $(this.list).attr('tabindex', '0')
                    .on('focus', function (e) {
                        me.focus(e);
                    });
            }
        }

        if (this.parent_focus) {
            this.list.parentNode.onclick = function (e) {
                me.focus();
            };
        }

        rcmail.triggerEvent('initlist', { obj: this.list });

        return this;
    },


    /**
     * Init list row and set mouse events on it
     */
    init_row: function (row) {
        row.uid = this.get_row_uid(row);

        // make references in internal array and set event handlers
        if (row && row.uid) {
            var self = this, uid = row.uid;
            this.rows[uid] = { uid: uid, id: row.id, obj: row };

            $(row).data('uid', uid)
            // set eventhandlers to table row (only left-button-clicks in mouseup)
                .mousedown(function (e) {
                    return self.drag_row(e, this.uid);
                })
                .mouseup(function (e) {
                    if (e.which == 1 && !self.drag_active && !$(e.currentTarget).is('.ui-droppable-active')) {
                        return self.click_row(e, this.uid);
                    }

                    return true;
                });

            // for IE and Edge (Trident) differentiate between touch, touch+hold using pointer events rather than touch
            if ((bw.ie || (bw.edge && bw.vendver < 75)) && bw.pointer) {
                $(row).on('pointerdown', function (e) {
                    if (e.pointerType == 'touch') {
                        self.touch_start_time = new Date().getTime();
                        return false;
                    }
                })
                    .on('pointerup', function (e) {
                        if (e.pointerType == 'touch') {
                            var duration = (new Date().getTime() - self.touch_start_time);
                            if (duration <= self.touch_event_time) {
                                self.drag_row(e, this.uid);
                                return self.click_row(e, this.uid);
                            }
                        }
                    });
            } else if (bw.touch && row.addEventListener) {
                row.addEventListener('touchstart', function (e) {
                    if (e.touches.length == 1) {
                        self.touchmoved = false;
                        self.drag_row(rcube_event.touchevent(e.touches[0]), this.uid);
                        self.touch_start_time = new Date().getTime();
                    }
                }, false);
                row.addEventListener('touchend', function (e) {
                    if (e.changedTouches.length == 1) {
                        var duration = (new Date().getTime() - self.touch_start_time);
                        if (!self.touchmoved && duration <= self.touch_event_time && !self.click_row(rcube_event.touchevent(e.changedTouches[0]), this.uid)) {
                            e.preventDefault();
                        }
                    }
                }, false);
                row.addEventListener('touchmove', function (e) {
                    if (e.changedTouches.length == 1) {
                        self.touchmoved = true;
                        if (self.drag_active) {
                            e.preventDefault();
                        }
                    }
                }, false);
            }

            // label the list row with the subject col as descriptive label
            if (this.aria_listbox) {
                var lbl_id = 'l:' + row.id;
                $(row)
                    .attr('role', 'option')
                    .attr('aria-labelledby', lbl_id)
                    .find(this.col_tagname()).eq(this.subject_column()).attr('id', lbl_id);
            }

            if (document.all) {
                row.onselectstart = function () {
                    return false;
                };
            }

            this.row_init(this.rows[uid]); // legacy support
            this.triggerEvent('initrow', this.rows[uid]);

            return true;
        }
    },


    /**
     * Init list column headers and set mouse events on them
     */
    init_header: function () {
        if (this.thead) {
            this.colcount = 0;

            if (this.fixed_header) { // copy (modified) fixed header back to the actual table
                $(this.list.tHead).replaceWith($(this.fixed_header).find('thead').clone());
                $(this.list.tHead).find('th,td').attr('style', '').find('a').attr('tabindex', '-1'); // remove fixed widths
            } else if (!bw.touch && this.list.className.indexOf('fixedheader') >= 0) {
                this.init_fixed_header();
            }

            var col, r, p = this;
            // add events for list columns moving
            if (this.column_movable && this.thead && this.thead.rows) {
                for (r = 0; r < this.thead.rows[0].cells.length; r++) {
                    if (this.column_fixed == r) {
                        continue;
                    }
                    col = this.thead.rows[0].cells[r];
                    col.onmousedown = function (e) {
                        return p.drag_column(e, this);
                    };
                    this.colcount++;
                }
            }
        }
    },

    /**
     * Set the scrollable parent object for the table's fixed header
     */
    container: window,

    init_fixed_header: function () {
        var clone = $(this.list.tHead).clone();

        if (!this.fixed_header) {
            this.fixed_header = $('<table>')
                .attr('id', this.list.id + '-fixedcopy')
                .attr('class', this.list.className + ' fixedcopy')
                .attr('role', 'presentation')
                .css({ position: 'fixed' })
                .append(clone)
                .append('<tbody></tbody>');
            $(this.list).before(this.fixed_header);

            var me = this;
            $(window).on('resize', function () {
                me.resize();
            });
            $(this.container).on('scroll', function () {
                var w = $(this);
                me.fixed_header.css({
                    marginLeft: -w.scrollLeft() + 'px',
                    marginTop: -w.scrollTop() + 'px',
                });
            });
        } else {
            $(this.fixed_header).find('thead').replaceWith(clone);
        }

        // avoid scrolling header links being focused
        $(this.list.tHead).find('a.sortcol').attr('tabindex', '-1');

        // set tabindex to fixed header sort links
        clone.find('a.sortcol').attr('tabindex', '0');

        this.thead = clone.get(0);
        this.resize();
    },

    resize: function () {
        if (!this.fixed_header) {
            return;
        }

        var column_widths = [];

        // get column widths from original thead
        $(this.tbody).parent().find('thead th,thead td').each(function (index) {
            column_widths[index] = $(this).width();
        });

        // apply fixed widths to fixed table header
        $(this.thead).parent().width($(this.tbody).parent().width());
        $(this.thead).find('th,td').each(function (index) {
            $(this).width(column_widths[index]);
        });

        $(window).scroll();
    },

    /**
     * Remove all list rows
     */
    clear: function (sel) {
        if (this.tagname == 'table') {
            var tbody = document.createElement('tbody');
            this.list.insertBefore(tbody, this.tbody);
            this.list.removeChild(this.list.tBodies[1]);
            this.tbody = tbody;
        } else {
            $(this.row_tagname() + ':not(.thead)', this.tbody).remove();
        }

        this.rows = {};
        this.rowcount = 0;
        this.last_selected = null;

        if (sel) {
            this.clear_selection();
        }

        // reset scroll position (in Opera)
        if (this.frame) {
            this.frame.scrollTop = 0;
        }

        // fix list header after removing any rows
        this.resize();
    },


    /**
     * 'remove' message row from list (just hide it)
     */
    remove_row: function (uid, sel_next) {
        var self = this, node = this.rows[uid] ? this.rows[uid].obj : null;

        if (!node) {
            return;
        }

        node.style.display = 'none';

        // Select next row before deletion, because we need the reference
        if (sel_next) {
            this.select_next(uid);
        }

        delete this.rows[uid];
        this.rowcount--;

        // fix list header after removing any rows
        clearTimeout(this.resize_timeout);
        this.resize_timeout = setTimeout(function () {
            self.resize();
        }, 50);
    },


    /**
     * Add row to the list and initialize it
     */
    insert_row: function (row, before) {
        var self = this, tbody = this.tbody;

        // create a real dom node first
        if (row.nodeName === undefined) {
            // for performance reasons use DOM instead of jQuery here
            var i, e, domcell, col,
                domrow = document.createElement(this.row_tagname());

            if (row.id) {
                domrow.id = row.id;
            }
            if (row.uid) {
                domrow.uid = row.uid;
            }
            if (row.className) {
                domrow.className = row.className;
            }
            if (row.style) {
                $.extend(domrow.style, row.style);
            }

            for (i = 0; row.cols && i < row.cols.length; i++) {
                col = row.cols[i];
                domcell = col.dom;
                if (!domcell) {
                    domcell = document.createElement(this.col_tagname());
                    if (col.className) {
                        domcell.className = col.className;
                    }
                    if (col.innerHTML) {
                        domcell.innerHTML = col.innerHTML;
                    }
                    for (e in col.events) {
                        domcell['on' + e] = col.events[e];
                    }
                }
                domrow.appendChild(domcell);
            }

            row = domrow;
        }

        if (this.checkbox_selection) {
            this.insert_checkbox(row);
        }

        if (before && tbody.childNodes.length) {
            tbody.insertBefore(row, (typeof before === 'object' && before.parentNode == tbody) ? before : tbody.firstChild);
        } else {
            tbody.appendChild(row);
        }

        this.init_row(row);
        this.rowcount++;

        // fix list header after adding any rows
        clearTimeout(this.resize_timeout);
        this.resize_timeout = setTimeout(function () {
            self.resize();
        }, 50);
    },

    /**
     * Update existing record
     */
    update_row: function (id, cols, newid, select) {
        var row = this.rows[id];
        if (!row) {
            return false;
        }

        var i, domrow = row.obj;
        for (i = 0; cols && i < cols.length; i++) {
            this.get_cell(domrow, i).html(cols[i]);
        }

        if (newid) {
            delete this.rows[id];
            domrow.uid = newid;
            domrow.id = 'rcmrow' + newid;
            this.init_row(domrow);

            if (select) {
                this.selection[0] = newid;
            }

            if (this.last_selected == id) {
                this.last_selected = newid;
            }
        }
    },

    /**
     * Add selection checkbox to the list record
     */
    insert_checkbox: function (row, tag_name) {
        var key, self = this,
            cell = document.createElement(this.col_tagname(tag_name)),
            chbox = document.createElement('input');

        chbox.type = 'checkbox';
        chbox.tabIndex = -1;
        chbox.onchange = function (e) {
            self.select_row(row.uid, key || CONTROL_KEY, true);
            e.stopPropagation();
            key = null;
        };
        chbox.onmousedown = function (e) {
            key = rcube_event.get_modifier(e);
        };

        cell.className = 'selection';
        // make the whole cell "touchable" for touch devices
        cell.onclick = function (e) {
            if (!$(e.target).is('input')) {
                key = rcube_event.get_modifier(e);
                $(chbox).prop('checked', !chbox.checked).change();
            }
            e.stopPropagation();
        };

        cell.appendChild(chbox);

        row.insertBefore(cell, row.firstChild);
    },

    /**
     * Enable checkbox selection
     */
    enable_checkbox_selection: function () {
        this.checkbox_selection = true;

        // Add checkbox to existing records if any
        var r, len, cell, rows,
            row_tag = this.row_tagname().toUpperCase();

        if (this.thead) {
            rows = this.thead.childNodes;
            for (r = 0, len = rows.length; r < len; r++) {
                if (rows[r].nodeName == row_tag && (cell = rows[r].firstChild)) {
                    if (cell.className == 'selection') {
                        break;
                    }
                    this.insert_checkbox(rows[r], 'thead');
                }
            }
        }

        rows = this.tbody.childNodes;
        for (r = 0, len = rows.length; r < len; r++) {
            if (rows[r].nodeName == row_tag && (cell = rows[r].firstChild)) {
                if (cell.className == 'selection') {
                    break;
                }
                this.insert_checkbox(rows[r], 'tbody');
            }
        }
    },

    /**
     * Set focus to the list
     */
    focus: function (e) {
        if (this.focused) {
            return;
        }

        this.focused = true;

        if (e) {
            rcube_event.cancel(e);
        }

        var focus_elem = null;

        if (this.last_selected && this.rows[this.last_selected]) {
            focus_elem = $(this.rows[this.last_selected].obj).find(this.col_tagname()).eq(this.subject_column()).attr('tabindex', '0');
        }

        // Un-focus already focused elements (#1487123, #1487316, #1488600, #1488620)
        if (focus_elem && focus_elem.length) {
            // We now fix this by explicitly assigning focus to a dedicated link element
            this.focus_noscroll(focus_elem);
        } else {
            // It looks that window.focus() does the job for all browsers, but not Firefox (#1489058)
            $('iframe,:focus:not(body)').blur();
            window.focus();
        }

        $(this.list).addClass('focus').removeAttr('tabindex');

        // set internal focus pointer to first row
        if (!this.last_selected) {
            this.select_first(CONTROL_KEY);
        }
    },


    /**
     * remove focus from the list
     */
    blur: function (e) {
        this.focused = false;

        // avoid the table getting focus right again (on Shift+Tab)
        var me = this;
        setTimeout(function () {
            $(me.list).attr('tabindex', '0');
        }, 20);

        if (this.last_selected && this.rows[this.last_selected]) {
            $(this.rows[this.last_selected].obj)
                .find(this.col_tagname()).eq(this.subject_column()).removeAttr('tabindex');
        }

        $(this.list).removeClass('focus');
    },

    /**
     * Focus the given element without scrolling the list container
     */
    focus_noscroll: function (elem) {
        var y = this.frame.scrollTop || this.frame.scrollY;
        elem.focus();
        this.frame.scrollTop = y;
    },


    /**
     * Set/unset the given column as hidden
     */
    hide_column: function (col, hide) {
        var method = hide ? 'addClass' : 'removeClass';

        if (this.fixed_header) {
            $(this.row_tagname() + ' ' + this.col_tagname() + '.' + col, this.fixed_header)[method]('hidden');
        }

        $(this.row_tagname() + ' ' + this.col_tagname() + '.' + col, this.list)[method]('hidden');
    },


    /**
     * onmousedown-handler of message list column
     */
    drag_column: function (e, col) {
        if (this.colcount > 1) {
            this.drag_start = true;
            this.drag_mouse_start = rcube_event.get_mouse_pos(e);

            rcube_event.add_listener({ event: 'mousemove', object: this, method: 'column_drag_mouse_move' });
            rcube_event.add_listener({ event: 'mouseup', object: this, method: 'column_drag_mouse_up' });

            // enable dragging over iframes
            this.add_dragfix();

            // find selected column number
            for (var i = 0; i < this.thead.rows[0].cells.length; i++) {
                if (col == this.thead.rows[0].cells[i]) {
                    this.selected_column = i;
                    break;
                }
            }
        }

        return false;
    },


    /**
     * onmousedown-handler of message list row
     */
    drag_row: function (e, id) {
        // don't do anything (another action processed before)
        if (!this.is_event_target(e)) {
            return true;
        }

        // handle only left-clicks
        if (rcube_event.get_button(e) != 0) {
            return true;
        }

        this.in_selection_before = e && e.istouch || this.in_selection(id) ? id : false;

        // selects currently unselected row
        if (!this.in_selection_before) {
            var mod_key = rcube_event.get_modifier(e);
            this.select_row(id, mod_key, true);
        }

        if (this.draggable && this.selection.length && this.in_selection(id)) {
            this.drag_start = true;
            this.drag_mouse_start = rcube_event.get_mouse_pos(e);

            rcube_event.add_listener({ event: 'mousemove', object: this, method: 'drag_mouse_move' });
            rcube_event.add_listener({ event: 'mouseup', object: this, method: 'drag_mouse_up' });

            if (bw.touch) {
                rcube_event.add_listener({ event: 'touchmove', object: this, method: 'drag_mouse_move' });
                rcube_event.add_listener({ event: 'touchend', object: this, method: 'drag_mouse_up' });
            }

            // enable dragging over iframes
            this.add_dragfix();
            this.focus();
        }

        return false;
    },


    /**
     * onmouseup-handler of message list row
     */
    click_row: function (e, id) {
        // sanity check
        if (!id || !this.rows[id]) {
            return false;
        }

        // don't do anything (another action processed before)
        if (!this.is_event_target(e)) {
            return true;
        }

        var now = new Date().getTime(),
            dblclicked = now - this.rows[id].clicked < this.dblclick_time;

        // unselects currently selected row
        if (!this.drag_active && !dblclicked && this.in_selection_before == id) {
            this.select_row(id, rcube_event.get_modifier(e), true);
        }

        this.drag_start = false;
        this.in_selection_before = false;

        // row was double clicked
        if (this.rowcount && dblclicked && this.in_selection(id)) {
            this.triggerEvent('dblclick');
            now = 0;
        } else {
            this.triggerEvent('click');
        }

        if (!this.drag_active) {
            // remove temp divs
            this.del_dragfix();
            rcube_event.cancel(e);
        }

        this.rows[id].clicked = now;
        this.focus();

        return false;
    },


    /**
     * Check target of the current event
     */
    is_event_target: function (e) {
        var target = rcube_event.get_target(e),
            tagname = target.tagName.toLowerCase();

        return !(target && (tagname == 'input' || tagname == 'img' || (tagname != 'a' && target.onclick) || $(target).data('action-link')));
    },


    /*
     * Returns thread root ID for specified row ID
     */
    find_root: function (uid) {
        var r = this.rows[uid];

        if (r && r.parent_uid) {
            return this.find_root(r.parent_uid);
        }

        return uid;
    },


    expand_row: function (e, id) {
        var row = this.rows[id],
            evtarget = rcube_event.get_target(e),
            mod_key = rcube_event.get_modifier(e),
            action = (row.expanded ? 'collapse' : 'expand') + (mod_key == CONTROL_KEY || this.multiexpand ? '_all' : '');

        // Don't treat double click on the expando as double click on the message.
        row.clicked = 0;

        this[action](row);
    },

    collapse: function (row) {
        var r, depth = row.depth,
            new_row = row ? row.obj.nextSibling : null;

        row.expanded = false;
        this.update_expando(row.id);
        this.triggerEvent('expandcollapse', { uid: row.uid, expanded: row.expanded, obj: row.obj });

        while (new_row) {
            if (new_row.nodeType == 1) {
                r = this.rows[new_row.uid];
                if (r && r.depth <= depth) {
                    break;
                }

                $(new_row).css('display', 'none');
                if (r.expanded) {
                    r.expanded = false;
                    this.triggerEvent('expandcollapse', { uid: r.uid, expanded: r.expanded, obj: new_row });
                }
            }
            new_row = new_row.nextSibling;
        }

        this.resize();
        this.triggerEvent('listupdate');

        return false;
    },

    expand: function (row) {
        var r, p, depth, new_row, last_expanded_parent_depth;

        if (row) {
            row.expanded = true;
            depth = row.depth;
            new_row = row.obj.nextSibling;
            this.update_expando(row.id, true);
            this.triggerEvent('expandcollapse', { uid: row.uid, expanded: row.expanded, obj: row.obj });
        } else {
            var tbody = this.tbody;
            new_row = tbody.firstChild;
            depth = 0;
            last_expanded_parent_depth = 0;
        }

        while (new_row) {
            if (new_row.nodeType == 1) {
                r = this.rows[new_row.uid];
                if (r) {
                    if (row && (!r.depth || r.depth <= depth)) {
                        break;
                    }

                    if (r.parent_uid) {
                        p = this.rows[r.parent_uid];
                        if (p && p.expanded) {
                            if ((row && p == row) || last_expanded_parent_depth >= p.depth - 1) {
                                last_expanded_parent_depth = p.depth;
                                $(new_row).css('display', '');
                                r.expanded = true;
                                this.update_expando(r.id, true);
                                this.triggerEvent('expandcollapse', { uid: r.uid, expanded: r.expanded, obj: new_row });
                            }
                        } else
                            if (row && (!p || p.depth <= depth)) {
                                break;
                            }
                    }
                }
            }
            new_row = new_row.nextSibling;
        }

        this.resize();
        this.triggerEvent('listupdate');

        return false;
    },


    collapse_all: function (row) {
        var depth, new_row, r;

        if (row) {
            row.expanded = false;
            depth = row.depth;
            new_row = row.obj.nextSibling;
            this.update_expando(row.id);
            this.triggerEvent('expandcollapse', { uid: row.uid, expanded: row.expanded, obj: row.obj });

            // don't collapse sub-root tree in multiexpand mode
            if (depth && this.multiexpand) {
                return false;
            }
        } else {
            new_row = this.tbody.firstChild;
            depth = 0;
        }

        while (new_row) {
            if (new_row.nodeType == 1) {
                if (r = this.rows[new_row.uid]) {
                    if (row && (!r.depth || r.depth <= depth)) {
                        break;
                    }

                    if (row || r.depth) {
                        $(new_row).css('display', 'none');
                    }
                    if (r.expanded) {
                        r.expanded = false;
                        if (r.has_children) {
                            this.update_expando(r.id);
                            this.triggerEvent('expandcollapse', { uid: r.uid, expanded: r.expanded, obj: new_row });
                        }
                    }
                }
            }
            new_row = new_row.nextSibling;
        }

        this.resize();
        this.triggerEvent('listupdate');

        return false;
    },


    expand_all: function (row) {
        var depth, new_row, r;

        if (row) {
            row.expanded = true;
            depth = row.depth;
            new_row = row.obj.nextSibling;
            this.update_expando(row.id, true);
            this.triggerEvent('expandcollapse', { uid: row.uid, expanded: row.expanded, obj: row.obj });
        } else {
            new_row = this.tbody.firstChild;
            depth = 0;
        }

        while (new_row) {
            if (new_row.nodeType == 1) {
                if (r = this.rows[new_row.uid]) {
                    if (row && r.depth <= depth) {
                        break;
                    }

                    $(new_row).css('display', '');
                    if (!r.expanded) {
                        r.expanded = true;
                        if (r.has_children) {
                            this.update_expando(r.id, true);
                            this.triggerEvent('expandcollapse', { uid: r.uid, expanded: r.expanded, obj: new_row });
                        }
                    }
                }
            }
            new_row = new_row.nextSibling;
        }

        this.resize();
        this.triggerEvent('listupdate');

        return false;
    },


    update_expando: function (id, expanded) {
        var expando = document.getElementById('rcmexpando' + id);
        if (expando) {
            expando.className = expanded ? 'expanded' : 'collapsed';
        }
    },

    get_row_uid: function (row) {
        if (!row) {
            return;
        }

        if (!row.uid) {
            var uid = $(row).data('uid');
            if (uid) {
                row.uid = uid;
            } else if (String(row.id).match(this.id_regexp)) {
                row.uid = RegExp.$1;
            }
        }

        return row.uid;
    },

    /**
     * get first/next/previous/last rows that are not hidden
     */
    get_next_row: function (uid) {
        if (!this.rowcount) {
            return false;
        }

        var last_selected_row = this.rows[uid || this.last_selected],
            new_row = last_selected_row ? last_selected_row.obj.nextSibling : null;

        while (new_row && (new_row.nodeType != 1 || new_row.style.display == 'none')) {
            new_row = new_row.nextSibling;
        }

        return new_row;
    },

    get_prev_row: function (uid) {
        if (!this.rowcount) {
            return false;
        }

        var last_selected_row = this.rows[uid || this.last_selected],
            new_row = last_selected_row ? last_selected_row.obj.previousSibling : null;

        while (new_row && (new_row.nodeType != 1 || new_row.style.display == 'none')) {
            new_row = new_row.previousSibling;
        }

        return new_row;
    },

    get_first_row: function () {
        if (this.rowcount) {
            var i, uid, rows = this.tbody.childNodes;

            for (i = 0; i < rows.length; i++) {
                if (rows[i].id && (uid = this.get_row_uid(rows[i])) && this.rows[uid]) {
                    return uid;
                }
            }
        }

        return null;
    },

    get_last_row: function () {
        if (this.rowcount) {
            var i, uid, rows = this.tbody.childNodes;

            for (i = rows.length - 1; i >= 0; i--) {
                if (rows[i].id && (uid = this.get_row_uid(rows[i])) && this.rows[uid]) {
                    return uid;
                }
            }
        }

        return null;
    },

    get_next: function () {
        var row;
        if (row = this.get_next_row()) {
            return row.uid;
        }
    },

    get_prev: function () {
        var row;
        if (row = this.get_prev_row()) {
            return row.uid;
        }
    },

    row_tagname: function () {
        var row_tagnames = { table: 'tr', ul: 'li', '*': 'div' };

        return row_tagnames[this.tagname] || row_tagnames['*'];
    },

    col_tagname: function (tagname) {
        var col_tagnames = {
            table: 'td', thead: 'th', tbody: 'td', '*': 'span',
        };
        return col_tagnames[tagname || this.tagname] || col_tagnames['*'];
    },

    get_cell: function (row, index) {
        return $(this.col_tagname(), row).eq(index + (this.checkbox_selection ? 1 : 0));
    },

    /**
     * selects or unselects the proper row depending on the modifier key pressed
     */
    select_row: function (id, mod_key, with_mouse) {
        var select_before = this.selection.join(','),
            in_selection_before = this.in_selection(id);

        if (!this.multiselect && with_mouse) {
            mod_key = 0;
        }

        if (!this.shift_start) {
            this.shift_start = id;
        }

        if (!mod_key) {
            this.shift_start = id;
            this.highlight_row(id, false);
            this.multi_selecting = false;
        } else {
            switch (mod_key) {
                case SHIFT_KEY:
                    this.shift_select(id, false);

                    break;
                case CONTROL_KEY:
                    if (with_mouse) {
                        this.shift_start = id;
                        this.highlight_row(id, true);
                    }

                    break;
                case CONTROL_SHIFT_KEY:
                    this.shift_select(id, true);

                    break;
                default:
                    this.highlight_row(id, false);

                    break;
            }

            this.multi_selecting = true;
        }

        if (this.last_selected && this.rows[this.last_selected]) {
            $(this.rows[this.last_selected].obj).removeClass('focused')
                .find(this.col_tagname()).eq(this.subject_column()).removeAttr('tabindex');
        }

        // unselect if toggleselect is active and the same row was clicked again
        if (this.toggleselect && in_selection_before && !mod_key) {
            this.clear_selection();
        }
        // trigger event if selection changed
        else if (this.selection.join(',') != select_before) {
            this.triggerEvent('select');
        }

        if (this.rows[id]) {
            $(this.rows[id].obj).addClass('focused');
            // set cursor focus to link inside selected row
            if (this.focused) {
                this.focus_noscroll($(this.rows[id].obj).find(this.col_tagname()).eq(this.subject_column()).attr('tabindex', '0'));
            }
        }

        if (!this.selection.length) {
            this.shift_start = null;
        }

        this.last_selected = id;
    },


    /**
     * Alias method for select_row
     */
    select: function (id) {
        this.select_row(id, false);
        this.scrollto(id);
    },


    /**
     * Select row next to the specified or last selected one
     * Either below or above.
     */
    select_next: function (uid) {
        var new_row = this.get_next_row(uid) || this.get_prev_row(uid);
        if (new_row) {
            this.select_row(new_row.uid, false, false);
        }
    },


    /**
     * Select first row
     */
    select_first: function (mod_key, noscroll) {
        var row = this.get_first_row();
        if (row) {
            this.select_row(row, mod_key, false);

            if (!noscroll) {
                this.scrollto(row);
            }
        }
    },


    /**
     * Select last row
     */
    select_last: function (mod_key, noscroll) {
        var row = this.get_last_row();
        if (row) {
            this.select_row(row, mod_key, false);

            if (!noscroll) {
                this.scrollto(row);
            }
        }
    },


    /**
     * Add all children of the given row to selection
     */
    select_children: function (uid) {
        var i, children = this.row_children(uid), len = children.length;

        for (i = 0; i < len; i++) {
            if (!this.in_selection(children[i])) {
                this.select_row(children[i], CONTROL_KEY, true);
            }
        }
    },


    /**
     * Perform selection when shift key is pressed
     */
    shift_select: function (id, control) {
        if (!this.rows[this.shift_start] || !this.selection.length) {
            this.shift_start = id;
        }

        var n, i, j, to_row = this.rows[id],
            from_rowIndex = this._rowIndex(this.rows[this.shift_start].obj),
            to_rowIndex = this._rowIndex(to_row.obj);

        // if we're going down the list, and we hit a thread, and it's closed, select the whole thread
        if (from_rowIndex < to_rowIndex && !to_row.expanded && to_row.has_children) {
            if (to_row = this.rows[(this.row_children(id)).pop()]) {
                to_rowIndex = this._rowIndex(to_row.obj);
            }
        }

        i = ((from_rowIndex < to_rowIndex) ? from_rowIndex : to_rowIndex),
        j = ((from_rowIndex > to_rowIndex) ? from_rowIndex : to_rowIndex);

        // iterate through the entire message list
        for (n in this.rows) {
            if (this._rowIndex(this.rows[n].obj) >= i && this._rowIndex(this.rows[n].obj) <= j) {
                if (!this.in_selection(n)) {
                    this.highlight_row(n, true);
                }
            } else {
                if (this.in_selection(n) && !control) {
                    this.highlight_row(n, true);
                }
            }
        }
    },


    /**
     * Helper method to emulate the rowIndex property of non-tr elements
     */
    _rowIndex: function (obj) {
        return (obj.rowIndex !== undefined) ? obj.rowIndex : $(obj).prevAll().length;
    },

    /**
     * Check if given id is part of the current selection
     */
    in_selection: function (id, index) {
        for (var n in this.selection) {
            if (this.selection[n] == id) {
                return index ? parseInt(n, 10) : true;
            }
        }

        return false;
    },


    /**
     * Select each row in list
     */
    select_all: function (filter) {
        if (!this.rowcount) {
            return false;
        }

        // reset but remember selection first
        var n, select_before = this.selection.join(',');
        this.selection = [];

        for (n in this.rows) {
            if (!filter || this.rows[n][filter] == true) {
                this.last_selected = n;
                this.highlight_row(n, true, true);
            } else {
                $(this.rows[n].obj).removeClass('selected').removeAttr('aria-selected');
            }
        }

        // trigger event if selection changed
        if (this.selection.join(',') != select_before) {
            this.triggerEvent('select');
        }

        this.focus();

        return true;
    },


    /**
     * Invert selection
     */
    invert_selection: function () {
        if (!this.rowcount) {
            return false;
        }

        // remember old selection
        var n, select_before = this.selection.join(',');

        for (n in this.rows) {
            this.highlight_row(n, true);
        }

        // trigger event if selection changed
        if (this.selection.join(',') != select_before) {
            this.triggerEvent('select');
        }

        this.focus();

        return true;
    },


    /**
     * Unselect selected row(s)
     */
    clear_selection: function (id, no_event) {
        var n, num_select = this.selection.length;

        // one row
        if (id) {
            for (n in this.selection) {
                if (this.selection[n] == id) {
                    this.selection.splice(n, 1);
                    break;
                }
            }
        }
        // all rows
        else {
            for (n in this.selection) {
                if (this.rows[this.selection[n]]) {
                    $(this.rows[this.selection[n]].obj).removeClass('selected').removeAttr('aria-selected');
                }
            }

            this.selection = [];
        }

        if (this.checkbox_selection) {
            $(this.row_tagname() + ':not(.selected) > .selection > input:checked', this.list).prop('checked', false);
        }

        if (num_select && !this.selection.length && !no_event) {
            this.triggerEvent('select');
            this.last_selected = null;
        }
    },


    /**
     * Getter for the selection array
     */
    get_selection: function (deep) {
        var res = $.merge([], this.selection);

        var props = { deep: deep, res: res };
        if (this.triggerEvent('getselection', props) === false) {
            return props.res;
        }

        // return children of selected threads even if only root is selected
        if (deep !== false && res.length) {
            for (var uid, uids, i = 0, len = res.length; i < len; i++) {
                uid = res[i];
                if (this.rows[uid] && this.rows[uid].has_children && !this.rows[uid].expanded) {
                    uids = this.row_children(uid);
                    for (var j = 0, uids_len = uids.length; j < uids_len; j++) {
                        uid = uids[j];
                        if (!this.in_selection(uid)) {
                            res.push(uid);
                        }
                    }
                }
            }
        }

        return res;
    },


    /**
     * Return the ID if only one row is selected
     */
    get_single_selection: function () {
        var selection = this.get_selection(false);

        if (selection.length == 1) {
            return selection[0];
        }

        return null;
    },


    /**
     * Highlight/unhighlight a row
     */
    highlight_row: function (id, multiple, norecur) {
        if (!this.rows[id]) {
            return;
        }

        if (!multiple) {
            if (this.selection.length > 1 || !this.in_selection(id)) {
                this.clear_selection(null, true);
                this.selection[0] = id;
                $(this.rows[id].obj).addClass('selected').attr('aria-selected', 'true');

                if (this.checkbox_selection) {
                    $('.selection > input', this.rows[id].obj).prop('checked', true);
                }
            }
        } else {
            var pre, post, p = this.in_selection(id, true);

            if (p === false) { // select row
                this.selection.push(id);
                $(this.rows[id].obj).addClass('selected').attr('aria-selected', 'true');

                if (this.checkbox_selection) {
                    $('.selection > input', this.rows[id].obj).prop('checked', true);
                }

                if (!norecur && !this.rows[id].expanded) {
                    this.highlight_children(id, true);
                }
            } else { // unselect row
                pre = this.selection.slice(0, p);
                post = this.selection.slice(p + 1, this.selection.length);

                this.selection = pre.concat(post);
                $(this.rows[id].obj).removeClass('selected').removeAttr('aria-selected');

                if (this.checkbox_selection) {
                    $('.selection > input', this.rows[id].obj).prop('checked', false);
                }

                if (!norecur && !this.rows[id].expanded) {
                    this.highlight_children(id, false);
                }
            }
        }
    },


    /**
     * Highlight/unhighlight all children of the given row
     */
    highlight_children: function (id, status) {
        var i, selected,
            children = this.row_children(id), len = children.length;

        for (i = 0; i < len; i++) {
            selected = this.in_selection(children[i]);
            if ((status && !selected) || (!status && selected)) {
                this.highlight_row(children[i], true, true);
            }
        }
    },


    /**
     * Handler for keyboard events
     */
    key_press: function (e) {
        if (!this.focused || $(e.target).is('input,textarea,select')) {
            return true;
        }

        var keyCode = rcube_event.get_keycode(e),
            mod_key = rcube_event.get_modifier(e);

        switch (keyCode) {
            case 37: // Left arrow
            case 39: // Right arrow
            case 40: // Up arrow
            case 38: // Down arrow
            case 63233: // "down" in Safari keypress
            case 63232: // "up" in Safari keypress
                // Stop propagation so that the browser doesn't scroll
                rcube_event.cancel(e);

                return this.use_arrow_key(keyCode, mod_key);
            case 32: // Space
                rcube_event.cancel(e);

                return this.select_row(this.last_selected, mod_key, true);
            case 36: // Home
                this.select_first(mod_key);

                return rcube_event.cancel(e);
            case 35: // End
                this.select_last(mod_key);

                return rcube_event.cancel(e);
            case 65: // Ctrl + A
                if (mod_key == CONTROL_KEY && this.multiselect) {
                    this.select_first(null, true);
                    this.select_last(SHIFT_KEY, true);

                    return rcube_event.cancel(e);
                }

                break;
            case 27: // Esc
                if (this.drag_active) {
                    return this.drag_mouse_up(e);
                }

                if (this.col_drag_active) {
                    this.selected_column = null;
                    return this.column_drag_mouse_up(e);
                }

                return rcube_event.cancel(e);
            case 9: // Tab
                this.blur();

                break;
            case 13: // Enter
                if (!this.selection.length) {
                    this.select_row(this.last_selected, mod_key, false);
                }

            default:
                this.key_pressed = keyCode;
                this.modkey = mod_key;
                this.triggerEvent('keypress');
                this.modkey = 0;

                if (this.key_pressed == this.BACKSPACE_KEY) {
                    return rcube_event.cancel(e);
                }
        }

        return true;
    },


    /**
     * Special handling method for arrow keys
     */
    use_arrow_key: function (keyCode, mod_key) {
        var new_row, selected_row = this.rows[this.last_selected];

        if (!selected_row) {
            // select the first row if none selected yet
            this.select_first(CONTROL_KEY);
        }
        // Safari uses the non-standard keycodes 63232/63233 for up/down, if we're
        // using the keypress event (but not the keydown or keyup event).
        else if (keyCode == 40 || keyCode == 63233) { // Down arrow
            new_row = this.get_next_row();
        } else if (keyCode == 38 || keyCode == 63232) { // Up arrow
            new_row = this.get_prev_row();
        } else if (keyCode == 39 && selected_row.has_children) { // Right arrow
            if (!selected_row.expanded) {
                this.expand_all(selected_row);
            } else {
                // jump to the first child
                new_row = this.get_next_row();
                mod_key = null;
            }
        } else if (keyCode == 37) { // Left arrow
            if (selected_row.expanded && selected_row.has_children && (!selected_row.parent_uid || !this.multiexpand)) {
                this.collapse_all(selected_row);
            } else if (selected_row.parent_uid) {
                // jump to the top-most or closest parent
                if (mod_key == CONTROL_KEY) {
                    new_row = this.rows[this.find_root(selected_row.uid)];
                } else {
                    new_row = this.rows[selected_row.parent_uid];
                }

                mod_key = null;
            }
        }

        if (new_row) {
            // simulate ctr-key if no rows are selected
            if (!mod_key && !this.selection.length) {
                mod_key = CONTROL_KEY;
            }

            this.select_row(new_row.uid, mod_key, false);
            this.scrollto(new_row.uid);
        }

        return false;
    },


    /**
     * Try to scroll the list to make the specified row visible
     */
    scrollto: function (id) {
        var row = this.rows[id] ? this.rows[id].obj : null;

        if (row && this.frame) {
            var scroll_to = Number(row.offsetTop),
                head_offset = 0;

            // expand thread if target row is hidden (collapsed)
            if (!scroll_to && this.rows[id].parent_uid) {
                var parent = this.find_root(this.rows[id].uid);
                this.expand_all(this.rows[parent]);
                scroll_to = Number(row.offsetTop);
            }

            if (this.fixed_header) {
                head_offset = Number(this.thead.offsetHeight);
            }

            // if row is above the frame (or behind header)
            if (scroll_to < Number(this.frame.scrollTop) + head_offset) {
                // scroll window so that row isn't behind header
                this.frame.scrollTop = scroll_to - head_offset;
            } else if (scroll_to + Number(row.offsetHeight) > Number(this.frame.scrollTop) + Number(this.frame.offsetHeight)) {
                this.frame.scrollTop = (scroll_to + Number(row.offsetHeight)) - Number(this.frame.offsetHeight);
            }
        }
    },


    /**
     * Handler for mouse move events
     */
    drag_mouse_move: function (e) {
        // convert touch event
        if (e.type == 'touchmove') {
            if (e.touches.length == 1 && e.changedTouches.length == 1) {
                e = rcube_event.touchevent(e.changedTouches[0]);
            } else {
                return rcube_event.cancel(e);
            }
        }

        if (this.drag_start) {
            // check mouse movement, of less than 3 pixels, don't start dragging
            var m = rcube_event.get_mouse_pos(e),
                limit = 10, selection = [], self = this;

            if (!this.drag_mouse_start || (Math.abs(m.x - this.drag_mouse_start.x) < 3 && Math.abs(m.y - this.drag_mouse_start.y) < 3)) {
                return false;
            }

            // remember dragging start position
            this.drag_start_pos = { left: m.x, top: m.y };

            // initialize drag layer
            if (!this.draglayer) {
                this.draglayer = $('<div>').attr('id', 'rcmdraglayer')
                    .css({ position: 'absolute', display: 'none', 'z-index': 2000 })
                    .appendTo(document.body);
            } else {
                this.draglayer.html('');
            }

            // get selected rows (in display order), don't use this.selection here
            $(this.row_tagname() + '.selected', this.tbody).each(function () {
                var uid = self.get_row_uid(this), row = self.rows[uid];

                if (!row || $.inArray(uid, selection) > -1) {
                    return;
                }

                selection.push(uid);

                // also handle children of (collapsed) trees for dragging (they might be not selected)
                if (row.has_children && !row.expanded) {
                    $.each(self.row_children(uid), function () {
                        if ($.inArray(this, selection) > -1) {
                            return;
                        }
                        selection.push(this);
                    });
                }

                // break the loop asap
                if (selection.length > limit + 1) {
                    return false;
                }
            });

            var row, subject,
                subject_col = self.subject_column(),
                subject_func = function (cell) {
                    if (cell) {
                        // remove elements marked with "skip-on-drag" class
                        cell = $(cell).clone();
                        $(cell).find('.skip-on-drag').remove();
                    }
                    return cell ? cell.text() : '';
                };

            // append subject (of every row up to the limit) to the drag layer
            $.each(selection, function (i, uid) {
                if (i > limit) {
                    self.draglayer.append($('<div>').text('...'));
                    return false;
                }

                row = self.rows[uid].obj;
                subject = '';

                $(row).children(self.col_tagname()).each(function (n, cell) {
                    if (subject_col < 0 || (subject_col >= 0 && subject_col == n)) {
                        if (subject = subject_func(cell)) {
                            return false;
                        }
                    }
                });

                // Subject column might be wrong, fallback to .subject
                if (!subject.length) {
                    subject = subject_func($(row).children('.subject').first());
                }

                if (subject.length) {
                    // remove leading spaces
                    subject = subject.trim();
                    // truncate line to 50 characters
                    subject = (subject.length > 50 ? subject.substring(0, 50) + '...' : subject);

                    self.draglayer.append($('<div>').text(subject));
                }
            });

            this.draglayer.show();
            this.drag_active = true;
            this.triggerEvent('dragstart');
        }

        if (this.drag_active && this.draglayer) {
            var pos = rcube_event.get_mouse_pos(e);
            this.draglayer.css({ left: (pos.x + 20) + 'px', top: (pos.y - 5 + (bw.ie ? document.documentElement.scrollTop : 0)) + 'px' });
            this.triggerEvent('dragmove', e ? e : window.event);
        }

        this.drag_start = false;

        return false;
    },


    /**
     * Handler for mouse up events
     */
    drag_mouse_up: function (e) {
        document.onmousemove = null;

        if (e.type == 'touchend') {
            if (e.changedTouches.length != 1) {
                return rcube_event.cancel(e);
            }
        }

        if (this.draglayer && this.draglayer.is(':visible')) {
            if (this.drag_start_pos) {
                this.draglayer.animate(this.drag_start_pos, 300, 'swing').hide(20);
            } else {
                this.draglayer.hide();
            }
        }

        if (this.drag_active) {
            this.focus();
        }
        this.drag_active = false;

        rcube_event.remove_listener({ event: 'mousemove', object: this, method: 'drag_mouse_move' });
        rcube_event.remove_listener({ event: 'mouseup', object: this, method: 'drag_mouse_up' });

        if (bw.touch) {
            rcube_event.remove_listener({ event: 'touchmove', object: this, method: 'drag_mouse_move' });
            rcube_event.remove_listener({ event: 'touchend', object: this, method: 'drag_mouse_up' });
        }

        // remove temp divs
        this.del_dragfix();

        this.triggerEvent('dragend', e);

        return rcube_event.cancel(e);
    },


    /**
     * Handler for mouse move events for dragging list column
     */
    column_drag_mouse_move: function (e) {
        if (this.drag_start) {
            // check mouse movement, of less than 3 pixels, don't start dragging
            var i, m = rcube_event.get_mouse_pos(e);

            if (!this.drag_mouse_start || (Math.abs(m.x - this.drag_mouse_start.x) < 3 && Math.abs(m.y - this.drag_mouse_start.y) < 3)) {
                return false;
            }

            if (!this.col_draglayer) {
                var lpos = $(this.list).offset(),
                    cells = this.thead.rows[0].cells;

                // fix layer position when list is scrolled
                lpos.top += this.list.scrollTop + this.list.parentNode.scrollTop;

                // create dragging layer
                this.col_draglayer = $('<div>').attr('id', 'rcmcoldraglayer')
                    .css(lpos).css({
                        position: 'absolute',
                        'z-index': 2001,
                        'background-color': 'white',
                        opacity: 0.75,
                        height: (this.frame.offsetHeight - 2) + 'px',
                        width: (this.frame.offsetWidth - 2) + 'px',
                    })
                    .appendTo(document.body)
                    // ... and column position indicator
                    .append($('<div>').attr('id', 'rcmcolumnindicator')
                        .css({
                            position: 'absolute',
                            'border-right': '2px dotted #555',
                            'z-index': 2002,
                            height: (this.frame.offsetHeight - 2) + 'px',
                        }));

                this.cols = [];
                this.list_pos = this.list_min_pos = lpos.left;
                // save columns positions
                for (i = 0; i < cells.length; i++) {
                    this.cols[i] = cells[i].offsetWidth;
                    if (this.column_fixed !== null && i <= this.column_fixed) {
                        this.list_min_pos += this.cols[i];
                    }
                }
            }

            this.col_draglayer.show();
            this.col_drag_active = true;
            this.triggerEvent('column_dragstart');
        }

        // set column indicator position
        if (this.col_drag_active && this.col_draglayer) {
            var i, cpos = 0, pos = rcube_event.get_mouse_pos(e);

            for (i = 0; i < this.cols.length; i++) {
                if (pos.x >= this.cols[i] / 2 + this.list_pos + cpos) {
                    cpos += this.cols[i];
                } else {
                    break;
                }
            }

            // handle fixed columns on left
            if (i == 0 && this.list_min_pos > pos.x) {
                cpos = this.list_min_pos - this.list_pos;
            }
            // empty list needs some assignment
            else if (!this.list.rowcount && i == this.cols.length) {
                cpos -= 2;
            }
            $('#rcmcolumnindicator').css({ width: cpos + 'px' });
            this.triggerEvent('column_dragmove', e ? e : window.event);
        }

        this.drag_start = false;

        return false;
    },


    /**
     * Handler for mouse up events for dragging list columns
     */
    column_drag_mouse_up: function (e) {
        document.onmousemove = null;

        if (this.col_draglayer) {
            (this.col_draglayer).remove();
            this.col_draglayer = null;
        }

        rcube_event.remove_listener({ event: 'mousemove', object: this, method: 'column_drag_mouse_move' });
        rcube_event.remove_listener({ event: 'mouseup', object: this, method: 'column_drag_mouse_up' });

        // remove temp divs
        this.del_dragfix();

        if (this.col_drag_active) {
            this.col_drag_active = false;
            this.focus();
            this.triggerEvent('column_dragend', e);

            if (this.selected_column !== null && this.cols && this.cols.length) {
                var i, cpos = 0, pos = rcube_event.get_mouse_pos(e);

                // find destination position
                for (i = 0; i < this.cols.length; i++) {
                    if (pos.x >= this.cols[i] / 2 + this.list_pos + cpos) {
                        cpos += this.cols[i];
                    } else {
                        break;
                    }
                }

                if (i != this.selected_column && i != this.selected_column + 1) {
                    this.column_replace(this.selected_column, i);
                }
            }
        }

        return rcube_event.cancel(e);
    },


    /**
     * Returns IDs of all rows in a thread (except root) for specified root
     */
    row_children: function (uid) {
        if (!this.rows[uid] || !this.rows[uid].has_children) {
            return [];
        }

        var res = [], depth = this.rows[uid].depth,
            row = this.rows[uid].obj.nextSibling;

        while (row) {
            if (row.nodeType == 1) {
                if (r = this.rows[row.uid]) {
                    if (!r.depth || r.depth <= depth) {
                        break;
                    }
                    res.push(r.uid);
                }
            }
            row = row.nextSibling;
        }

        return res;
    },


    /**
     * Creates a layer for drag&drop over iframes
     */
    add_dragfix: function () {
        $('iframe').each(function () {
            $('<div class="iframe-dragdrop-fix"></div>')
                .css({
                    background: '#fff',
                    width: this.offsetWidth + 'px',
                    height: this.offsetHeight + 'px',
                    position: 'absolute',
                    opacity: '0.001',
                    zIndex: 1000,
                })
                .css($(this).offset())
                .appendTo(document.body);
        });
    },


    /**
     * Removes the layer for drag&drop over iframes
     */
    del_dragfix: function () {
        $('div.iframe-dragdrop-fix').remove();
    },


    /**
     * Replaces two columns
     */
    column_replace: function (from, to) {
        // only supported for <table> lists
        if (!this.thead || !this.thead.rows) {
            return;
        }

        var len, cells = this.thead.rows[0].cells,
            elem = cells[from],
            before = cells[to],
            td = document.createElement('td');

        // replace header cells
        if (before) {
            cells[0].parentNode.insertBefore(td, before);
        } else {
            cells[0].parentNode.appendChild(td);
        }
        cells[0].parentNode.replaceChild(elem, td);

        // replace list cells
        for (r = 0, len = this.tbody.rows.length; r < len; r++) {
            row = this.tbody.rows[r];

            elem = row.cells[from];
            before = row.cells[to];
            td = document.createElement('td');

            if (before) {
                row.insertBefore(td, before);
            } else {
                row.appendChild(td);
            }
            row.replaceChild(elem, td);
        }

        // update subject column position
        if (this.subject_col == from) {
            this.subject_col = to > from ? to - 1 : to;
        } else if (this.subject_col < from && to <= this.subject_col) {
            this.subject_col++;
        } else if (this.subject_col > from && to >= this.subject_col) {
            this.subject_col--;
        }

        if (this.fixed_header) {
            this.init_header();
        }

        this.triggerEvent('column_replace');
    },

    subject_column: function () {
        return this.subject_col + (this.checkbox_selection ? 1 : 0);
    },

};

rcube_list_widget.prototype.addEventListener = rcube_event_engine.prototype.addEventListener;
rcube_list_widget.prototype.removeEventListener = rcube_event_engine.prototype.removeEventListener;
rcube_list_widget.prototype.triggerEvent = rcube_event_engine.prototype.triggerEvent;

// static
rcube_list_widget._instances = [];
